Guild Wars 2

If I put an offensive infusion in a weapon, will I only get the stat bonus if the weapon is swapped “on”?

If so, the best place to start putting offensive infusions would be in trinkets since they are never swapped “off”, correct?

I’m beginning the process of crafting fine offensive infusions and would like to know where best to start placing the initial ones.

1) yes. Only if weapon active.
2) It depends. If you never change trinkets then yes it’s reasonable to start with it.